Restore disks or from the OS X installation disk.
Run Disk Utility, the one on the Restore/Installation disk, to see if there is a problem with the internal HD.
Seems you found AV software that is more of a problem than the problem it is supposed to cure.
Currently there is no active virus problem for OS X.
i installed avast in my mac..it scanned and after dat i shut down my mac but avast wouldnt quit so i forced quit it!!
later i switch on m mac..it gets stuck in start up page forever and ever with the wheel spinning!!
my desktop wouldnt appear
i tried all de actions given in de mac guide ntn seems to work...plz help!